Bon voyage party for Bertha draws 5,000 people to SR 99 tunnel site

Start with some sun, soil and celebration. Then add Bertha, the massive machine that will dig the SR 99 tunnel beneath downtown Seattle, and 5,000 of her closest friends. The result is a party big enough for the biggest tunnel-builder the world has ever seen.

Thousands of people descended on the SR 99 tunnel launch pit on Saturday for a chance to see Bertha up-close before she starts tunneling later this month. Guests talked to project staff, learned about the project and walked around the construction site, including one of the walkways that spans the 80-foot-deep pit where Bertha will soon start tunneling.

The event included activities designed to teach kids about science and engineering. Guests also had the opportunity to sign their name on one of the concrete segments that will form the tunnel’s walls.

Tunneling will start after final testing is complete, likely by the end of July. The tunnel is scheduled to open to drivers in late 2015. You can track all of the action on our construction cameras. And don’t forget Bertha is on Twitter. Followers of @BerthaDigsSR99 will continue to get regular updates straight from Bertha herself as she prepares to start digging beneath Seattle.